Instrumentation. Test 6 – Online Maritime Tests

The picture shows a liquid filled thermometer. Liquid filled thermometers and manometers are often installed onboard ships. What is the main purpose by the liquid filling of such pointer instruments?

Compensating for changes in ambient temperature
Reduce mechanical wear on the internal parts caused by vibration
Avoid water penetration from outside
Keep the rear side of the front glass clean

This block diagram illustrates an elementary control system. What do we call such system in general?

Scmitt trigger
Closed loop feed back system
Open loop feed back system
Feed forward system

These circuit diagrams illustrate four different methods of wiring between a Pt 100 temperature sensor and its signal processing electronics. Which of the wiring methods gives the best measuring accuracy?

Figure 2
Figure 1
Figure 3
Figure 4

Temperatures are often measured by means of platinum resistance sensors. These curves are all calibration curves. Which of the curves is calibration curve for a Pt 100 sensor?

Figure 1
Figure 4
Figure 3
Figure 2

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